Micro-Raman mapping and analysis of indentation-induced phase transformations in germanium Conference Paper uri icon


  • Although it has been confirmed by diamond anvil cell experiments that germanium transforms under hydrostatic pressure from the normal diamond cubic phase (Ge-I) to the metallic -tin phase (Ge-II) and re-transforms to Ge-III (ST12 structure) or Ge-IV (BC8 structure) during release of the pressure, there are still controversies about whether the same transformations occur during nanoindentation. Here, we present new evidence of indentation-induced phase transformations in germanium. Nanoindentation experiments were performed on a (100) Ge single crystal using two triangular pyramidal indenters with different tip angles - the common Berkovich and the sharper cube-corner. Although the indentation load-displacement curves do not show any of the characteristics of phase transformation that are well-known for silicon, micro-Raman spectroscopy in conjunction with scanning electron microscopy reveals that phase transformations to amorphous and metastable crystalline phases do indeed occur. However, the transformations are observed reproducibly only for the cube-corner indenter. 2005 Materials Research Society.

published proceedings

  • Materials Research Society Symposium Proceedings

author list (cited authors)

  • Jang, J. I., Lance, M. J., Wen, S., Huening, J. J., Nemanich, R. J., & Pharr, G. M.

complete list of authors

  • Jang, JI||Lance, MJ||Wen, S||Huening, JJ||Nemanich, RJ||Pharr, GM

publication date

  • June 2005